“Time is the friend of stocks, the enemy of bonds” has been cited in print since at least 2008 and is of unknown origin. The saying includes the word “time,” but probably means “time” plus “inflation.” Long-term inflation will increase stocks, but bonds remain fixed.
 
   
Google Books
Investment Analysis and Portfolio Management
By Prasanna Chandra
Tata Mcgraw-Hill
2008
Pg. 23 (Proverbial Investment Wisdom):
Time is the friend of stocks; the enemy of bonds.
   
a knol by Linus Nilsson
Wall Street Adages
Quotes from the Street
Last edited: Nov 30, 2008 12:26
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Time is the friend of stocks, the enemy of bonds.
 
Bronte Capital
Friday, September 3, 2010
Gold price and bond price - a comment on the efficient market hypothesis
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David Pearson said…
What “squares the circle” of bonds and gold is an absence of long term real growth expectations. Long term real growth is the enemy of bonds and gold, and the friend of stocks.
September 5, 2010 12:14 AM
 
Syracuse (NY) Post-Standard
Investor’s Edge: Select bonds that will hold value
Published: Monday, September 06, 2010, 4:36 PM
“Time is the friend of stocks; the enemy of bonds.”
— Wall Street adage